The present invention relates to a protective element for hand-held power tool.
Protective elements of the above mentioned general type are known in the art. One such protective element is disclosed for example in DE-PS 2,216,990. The protective element shown in this reference has two elongated openings with increased portion for insertion of heads of holding screws. The holding screws extend through two guide slots in a guide carriage and can connect the guide carriage with the protective element. The distance of the guide slots and the distance of the increased portions of the longitudinal openings are different. Parts of the guide slots and the increased portions are brought into alignment with one another by rotation of the protective element relative to the guide carriage in the contact plane between the protective element and the guide carriage. In any other normal position of use, the screws extending through the guide slots and the longitudinal openings cannot be brought on the increased portions. The holding screws which engage through the longitudinal openings into the protective element and the guide slot into the guide carriage and hold the former with the latter together with the screwed wing nuts, can allow a displacement of the guide carriage relative to the protective member after slight release of the wing nuts. Because of the above described different distances, an undesirable release of the protective element from the guide carriage by simultaneous withdrawal of the head of the holding screw from the increased portions in the protective element is prevented with relatively high reliability. Only exactly determined relative position between the protective element and the guide carriage is required, in which the heads of both holding screws can extend through the increased portions in the protective elements. The disadvantage of this construction is the complicated mounting. First, the head of one holding screw must be inserted through one increased portion. Then, the holding screw must be displaced to another end of the longitudinal opening. Then, the guide carriage must be turned around the holding screw until the other holding screw has such a distance from the first holding screw that its head can be inserted through the associated increased portion. After this, the guide carriage is again turned to its working position in which the longitudinal slots of the carriage are directed substantially normal to the opening edge of the protective element. Thus the second holding screw moves into the second longitudinal opening.
In a protective element in accordance with the DE-GM 7,909,078, the increased portions for the heads of the holding screws are provided in the protective element, which in the lateral view of the shaft ends of the holding screws have a shape corresponding to the shape of the screw head. The holding screws can be turned only relative to its normal position by substantially 90.degree. and brought through the increased portions. Here a turning movement of the screws is needed. It is also guaranteed that the protective element and the guide carriage during relative adjustment cannot be unintentionally loosened. In this construction, however, again a relatively expensive mounting is needed. Both the above described constructions have the same feature that they require an exact mounting process. An operator who does not have special knowledge cannot recognize how he can assemble the guide carriage and the protective element with the aid of the screws.